Benzoxepino or benzthiapino[4,3-b]-pyrrole-2-acetic acids, for example, 1,7-dimethyl-4,10-dihydro-10-oxo-1H-[1]-benzoxepino[4,3-b]pyrrole-2-acetic acid ##STR1## are found to be potent analgesic and anti-inflammatory agents with very low ulcerogenic side effect. These compounds and the composition, method of use and process for preparation thereof have been the subject matter of a pending application U.S. Ser. No. 279,140 filed June 30, 1981. Although the compounds have been prepared by a satisfactory method as disclosed in U.S. Ser. No. 279,140, involving the intermediate pyrrole .alpha.-oxoacetate (I), ##STR2## the overall yields have been unsatisfactory and therefore economically unviable. Accordingly, it is the object of this invention to provide new and improved processes for making the active compounds.